Twenty-four-hour clock



July 3, 1928.

F. A. HELIN TWENTY-FOUR-HOUR CLOCK Filed Sept. 17, 1926 INVENTOR E'aIwAHeZUz/ ATTORN EY5.

Patented July 3, 1928.

PATENT OFFICE.

FRANCIS A. HELIN, on WATERTOWN, NEW YORK.

TWENTY-FGUR-I'IOUR CLOCK.

Application filed September 17, 1926. Serial No. 136,113.

This invention relates particularly to ciocks of the twenty-four-hourtype wherein the dial is provided with twenty-four graduations which are traversed by an hour- 'indicating pointer once in each twenty-four hours. i 7

An object of the present invention is to provide a clock of this type having a dial with its hour graduations arranged in an endless series and having apoi nter driven by a clock movement to traverse continuously along said series, the dial graduations and their markings being designed to clearly distinguish the diurnal hours from the nocturnal hours, and also the a. m. hours from the p. 111. hours. I

A further object of the invention is to providea clock of simple structure having twenty-four hour graduations arranged in an endless series and a. pointer mechanism driven by a. standard twelve-hour clock movement and adapted to move a pointer continuously in an endless path along said series of .graduati'ons.

In the drawings, Fig. lis a front face View of the clock; and I F ig. 2a vertical section taken on the line 2-2 of Fig. 1.

Referring to the various parts of the clock by numerals, 1 designates the clock casing. This casing is vertically elongated in form, rectangular at its lower end and semi-circular at its upper end in face view. The rear side of the casing is closed by a wall 2 and the front side is closed by a glass panel 3. A clock movement 4 is mounted within the upper curved end of the casing. This clock movement is of the standard twelvehour type and has its hour arbor and ts minute arbor disposed concentrically with relation to the semi-circular upper end of the casing. The minute arbor is in the form of a slender central spindle 5 and the hour arbor is in the form of a sleeve 6 surrounding the minute arbor. Mounted upon the hour arbor 6 and keyed to rotate with t 1s a driving sprocket wheel 7 of relatively large diameter. Adjacent the lower end of the casing 1 a stub shaft 8 is mounted upon the rear wall 2 and projects forwardly. This shaft 8 extends parallel to the two arbors and is disposed in the same vertical foreand-aft plane with them. A follower sprocket wheel 9 is mounted to rotate upon a journal portion 10 at the free end of the shaft 8. The follower wheel 9 is of the same diameter as the driving wheel '7 and both are located in the same vertical planes An endless chain 11 is trained around both wheels and extends in straight parallel lines between them. The length of the chain 11 is equal to twice the circumference of the driving wheel 7.

Located inwardly of the glass panel 3, just in advance the sprocket wheels and their chain, is a dial plate 12. The outer edge of this plate conforms in outline to the casing 1, being rectangular at its lower end and semi-circular at its upperend. The plate is secured within the casing in any suitable manner. 5 Centrally it is formed with a large, vertically elongated opening 13 conforming in outline to the course of the chain 11 and in register with it. Located within the opening 13 anddisposed in the same plane with the plate 12 is an inner dial and cover plate 1 1. The plate 14 has an outline similarto the opening 13 but slightly smaller in order to define a continuous slot 15 between the two plates and extending along the coarse of the chain. 11. The plate 1 1 is held in place in any suitable way. In the present instance it is attached by screws 16 to posts 17 which project forwardly from the rear wall 2. At

the center of its upper, curved end, the plate 14 is formed with an opening 18 through which the minute arbor 5 projects. A min ute hand 19 is fixed to the outer end of the arbor at the front face of the dial plate. The chain 11 forms a carrier for an hour pointer 20. This pointer is connected to one of the links of the chain in any suitable manner, as by a post 21 which projects through the slot 15. The'pointor is directed outwardly toward the side of the clock face and extends across the slot 15 at the front faces of the two dial plates.

The inner dial plate 14 is marked as at 22 to indicate minute graduations arranged in a continuous circular series concentric with the minute arbor and surrounding the minute hand 19. In the. present instance there are sixty of these graduations numbered in fives from 5 to 60. numbered in a different order. The graduations are traversed by the minute hand and each revolution of the hand indicates the passage of one hour as in the case of a standard clock. The outer dial plate 12 is marked with two parallel continuous lines 23 extending entirely around the oblong opening 13 and parallel to the course of the chain 11.

These lines define the path of the outer end of the hour pointer 20 and the entire length of said path is graduated into twenty-four one-hour spaces by transverse marks 24. The uppermost and the lowermost of the hour marks 24; upon the dial are located upon a vertical line extending through the centers of the wheels 7 and 9. These two marks are both numbered 12, the caption Noon being placed over the upper mark and the caption Night placed beneath the lower mark. The graduation marks to the right of the vertical center line are numbered consecutively l to 11, downwardly from the upper 12 mark. Those to the left of said line are nmnbered? to 11 upwardly from the lower 12 mark. The halves of the dial at the right and left of the center line are marked, respectively, p. m. and a. m. 'These marks are placed approximately midway the vertical length of the dial just above the 6 marks at opposite sides thereof. The lines 23 are'scored more heavily or more darkly belowthe 6 marks than above said marks, to graphically indicate that the gradnations within the lower half of the dial represent the nocturnal hours and clearly distinguish them from the diurnal or day,- light hours indicated upon the upper hall of the dial.v

WVhen the clock movement is running, the driver wheel 7 will be rotated continuously by the hour arbor 6 and said wheel will drive the carrier chain 11 and cause the hour pointer 20 to traverse the continuous lines 23 and indicate thefhours marked therealong.

The minute hand 19 is adjusted with rela-' tion to the hour pointer 20 so as to accurately indicate the ninute time within the hour indicated by the pointer. The hour dial and the moving pointer 20 represent graphically the movement of the sun relatively to the earth. A horizontal line through the two 6 marks may be considered the horizon. The path of the pointer above this line represents the diurnal arc with its highest point at 12 (noon) and the path below the line represents the nocturnal arc with its lowest point at 12 (midnight). These points are thus logically positioned upon the dial so that there is no danger of confusing them.

While I have shown and described a preferred 'embodimentof my invention, I re serve the right to make such changes in the mechanism. and in the arrangement and numbering of the dial graduations as will lie within the scope of the claim.

What I claim is:

A clock of the type set forth comprising a clock movement including a continuously rotating hour arbor making one rotation in twelve hours; a driver wheel fixed to the arbor to rotate with it; an endless carrier trained around said wheel and guided in an elongated course, the length 01" said carrier being equal to twice the circumference of the wheel; an hour pointer attached to the carrier; and an hour dial marked 'with twenty-four hour graduations arranged in a continuous series extending around the course of the carrier and adapted to be traversed continuously by the hour pointer.

In testimony whereof I hereunto aflix my signature.

FRANCIS A. HELIN. 

